The invention relates to a gene capable of enhancing salicylic acid-induced cell death in a plant cell and contributing to resistance to the fungal virulence factor deoxynivalenol, resistance to Fusarium fungi and Fusarium head blight disease, and a recombinant construct including the gene. The invention also relates to plant cells transformed with the gene, and plant material including plant cell cultures, seeds, and plants comprising the transformed plant cells.
The phenolic compound salicylic acid is a key signaling molecule for plant disease resistance. Salicylic acid accumulation is induced by pathogen attacks and other stress conditions (Delaney et al. 1994). Exogenous application of salicylic acid or its analogs such as benzo (1,2,3) thiadiazole-7-carothioic acid induces disease resistance in plants (White 1979; Gorlach et al. 1996; Lawton et al. 1996). Salicylic acid postively regulates cell death (Vlot et al. 2009) and in doing so it inhibits the spread of biotrophic pathogens. It is an important component of the defence response to biotrophs and hemibiotrophs such as F. graminearum (Makandar et al. 2012). F. graminearum is the causal agent of the economically devastating Fusarium head blight (FHB) disease of cereals; this pathogen is hemibiotrophic, with a short biotrophic phase preceding a necrotrophic phase (where they feed off dead plant tissue). This disease is important because it causes both yield loss and toxin contamination of small grain cereals such as wheat and barley. Enhancing resistance to the toxin deoxynivalenol (DON) is known to improve resistance to disease. Given the economic importance of FHB, several control strategies have been developed to prevent FHB epidemics. However, the use of host resistance is considered to be the most effective means to control FHB and trichothecene accumulation in wheat. DON is phytotoxic and resistance to DON enhances resistance to Fusarium and FHB disease. US2007/0044171 discloses thousands of recombinant polynucleotides that are described as being useful for improvement of plants.
It is the object of the invention to discover novel genes that enhance salicylic acid-induced immunity and contribute to resistance to DON and FHB.